Phosphomimetic mutations in the Akt1 phosphorylation site induced cytoplasmic localization of p21.

<p>(A) Representative immuno-fluorescence images (60x objective) of ectopically expressed p21 protein 24 hours post-transfection of NIH3T3 cells using anti-Myc-Tag antibody illustrate nuclear, cytoplasmic, and nuclear plus cytoplasmic p21 localization. (B) Recombinant mouse p21 proteins were expressed in NIH3T3. Localization of the indicated p21 protein was detected by immuno-staining with an anti-Myc-Tag antibody, 24 hours after transfection. In addition to wild-type (wt) p21 and the T140V (T/V) and S141A (S/A) p21 mutants, T140E (T/E) and S141D (S/D) p21 phosphomimetic mutants, and a double phosphomimetic mutant (T/E+S/D) were also tested. More than 100 cells were scored for each transfection.